Charge more for LTS support. That’ll chase people onto your new systems.
I’ve seen this play out badly before. It costs real money to keep engineers knowledgeable of what should rightfully be EOL systems. If you can make your laggard customers pay extra for that service, you can take care of those engineers.
The reward for refactoring shitty code is supposed to be not having to deal with it anymore. If you have to continue dealing with it anyway, then you pay for every mistake for years even if you catch it early. You start shutting down the will for continuous improvement. The tech debt starts to accumulate because it can never be cleared, and trying to use makes maintenance five times more confusing. People start wanting more Waterfall design to try to keep errors from ever being released in the first place. It’s a mess.
Models aren't code though. I'm sure there's code around it but for the most part models aren't maintained, they're just replaced. And a system that was state of the art literally yesterday is really hard to characterize as "rightfully EOL".
That doesn’t stop manufacturers from getting rid of parts that have no real equivalent elsewhere in their catalog. Sometimes they do, but at the end of the day you’re at their mercy. Or you have strong enough ties to their management that they keep your product forever, even later when it’s hurting them to keep it.
and then phase them out over time
would have reduced usage by 99% anyway
now it all distracts from the gpt5 launch